It can't possibly be a bug because your logic would mean that a vendor is never able to add new command-line options. If you can show me the ANSI or UNIX specification where it defines white space parameters, then you have a case.

More proof? What if you were parsing smit output? We both know that changes. Are you going to claim that smit is full of bugs because it doesn't work the same way as it did in the 80s?